Gray whale wanders into San Diego Bay

A gray whale migrating along the California coast swam into the shallower waters of San Diego Bay early Monday, April 19, 2010. It is seen here "spyhopping" and swimming in the waters between Shelter Island and Harbor Island.
— John Gibbins / Union-Tribune

A gray whale migrating along the California coast swam into the shallower waters of San Diego Bay early Monday, April 19, 2010. It is seen here "spyhopping" and swimming in the waters between Shelter Island and Harbor Island.
— John Gibbins / Union-Tribune

San Diego  A large gray whale has been exploring San Diego Bay since at least early Monday morning, the U.S. Coast Guard and others said.

The news encouraged officials at the Maritime Museum of San Diego, who enjoyed a boost in attendance for their boat tours of the bay when a whale showed up about this time last year.

“Hopefully, we will have another great spring,” said Robyn Gallant, marketing director at the museum.

A fisherman spotted the latest whale about 7:40 a.m. near Shelter Island, said Coast Guard Petty Officer Henry Dunphy. The agency doesn’t track wayward whales, which sometimes spend days or even weeks in the bay during their annual migration north from Baja California.

“It’s free to move around,” said Dunphy, who asked that boaters not to come within 100 yards of the whale. “Keep your distance and give it room to move.”

Before midday, word had circulated at the museum that two whales were swimming in the bay, but that hasn’t been confirmed. Video footage taken from local TV stations’ helicopters show only one whale.

Last spring, a 30-foot whale nicknamed Diego spent nearly a month in the bay, generating business for harbor cruise companies and creating quite a buzz along the waterfront. When Diego departed, a manager at Anthony’s Fish Grotto on the Embarcadero invited the whale to return this year and attract more customers to the bayside restaurant.

About 20,000 gray whales pass San Diego each year in late winter and spring as they swim between Baja and Alaska, where they spend the summer before returning south for the calving season.